Method for manufacturing slide fastener

ABSTRACT

There is provided a slide fastener and a method for manufacturing a slide fastener. A slide fastener is provided with: a pair of fastener tapes; a pair of fastener element rows provided respectively on the opposing tape-side edges of the pair of fastener tapes and having a plurality of fastener elements; and a slider configured to engage and disengage the pair of fastener element rows with and from each other. Each of the fastener element rows is composed of a monofilament which is made of synthetic resin. The monofilament has, on the surface thereof, a surface layer which can be colored with dyes. A roughened surface having a number of concaves is formed on the surfaces of the surface layer.

This application is a divisional application of U.S. application Ser.No. 13/805,687, now U.S. Pat. No. 8,966,719 issued Mar. 3, 2015, whichis a national stage application of PCT/JP2010/061200, both of which areincorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a slide fastener and a method formanufacturing the same, and more particularly, to a slide fastenerhaving fastener elements on which matting is performed and a method formanufacturing the same.

BACKGROUND ART

As one type of matting for fastener elements of the related art, thereis a method of polishing the monofilament with using a brush beforeshaping of a fastener element row, to scrape the surface of themonofilament and to form microscopic concaves and convexes on thesurface of the monofilament.

SUMMARY OF INVENTION Problems to be Solved by Invention

In the matting processing of the related art, the polishing using abrush is used for scraping the surface of a monofilament to whichcolorant is kneaded (hereinafter, referred to as a spin-dyeingmonofilament) and forming microscopic concaves and convexes on thesurface thereof. This is because the color on the surface is maintainedeven after the surface of the spin-dyeing monofilament is scraped.However, in order to knead the colorant, it is necessary to increase thecost of raw materials and to manage the inventory of plural colors ofcolorants, thereby resulting in an increase in the manufacturing cost.To overcome these problems, there was an attempt to polish amonofilament into which colorant are not kneaded (hereinafter, referredto as a natural monofilament; see FIG. 11 and FIG. 12) using a brush andthen to dye the natural monofilament. However, since the surface layerwhich is formed on the surface of the natural monofilament and can becolored with dyes is scraped, a uniform dye cannot be obtained (see FIG.13 and FIG. 14).

Here, the surface layer refers to a layer which is formed by rapidcooling of the surface side of the extrusion-molded monofilament duringcooling of the monofilament, has a rough structure, and can be coloredwith dyes. In addition, the inner part of the surface layer is slowlycooled, and thus is a layer that has a precise structure and is noteasily colored with dyes.

The present invention has been made in mind the foregoing problems, andan object of the present invention is to provide a slide fastener and amethod for manufacturing the same, in which both dying and matting canbe performed on the fastener element row, thereby reducing themanufacturing cost of the slide fastener.

Means for Solving Problems

The object of the present invention is achieved by the followingconfigurations.

(1) A slide fastener including: a pair of fastener tapes; a pair offastener element rows provided on respective opposing tape-side edges ofthe pair of fastener tapes, the pair of fastener element rows having aplurality of fastener elements; and a slider configured to engage anddisengage the pair of fastener element rows with and from each other,wherein each of the pair of fastener element rows is comprised of amonofilament which is made of synthetic resin, wherein the monofilamenthas a surface layer on a surface thereof, the surface layer being ableto be colored with dyes, and wherein a roughened surface having a numberof concaves is formed on a surface of the surface layer.

(2) In the slide fastener according to (1), wherein the roughenedsurface is formed by blast processing.

(3) In the slide fastener according to (1) or (2), wherein an averageroughness degree of the roughened surface ranges from 0.1 μm to 6.0 μm.

(4) In the slide fastener according to any one of (1) to (3), wherein asynthetic resin material for the monofilament is polyester or nylon.

(5) A method for manufacturing a slide fastener comprising: a pair offastener tapes; a pair of fastener element rows provided respectiveopposing tape-side edges of the pair of fastener tapes, the pair offastener element rows having a plurality of fastener elements; and aslider configured to engage and disengage the pair of fastener elementrows with and from each other, wherein each of the pair of fastenerelement rows is comprised of a monofilament which is made of syntheticresin, the method including a step of forming the monofilament byextrusion molding; a step of forming a roughened surface having a numberof concaves on a surface of the monofilament by performing blastprocessing on the surface of the monofilament; a step of shaping themonofilament into the fastener element row; and a step of dying thefastener element row.

Advantageous Effects of Invention

According to the slide fastener of the present invention, the roughenedsurface having a number of concaves is formed on the surface of thesurface layer of the monofilament. Consequently, it is possible toperform matting on the monofilament without scraping the surface layer.Accordingly, both dying and matting can be performed on the fastenerelement row. In addition, since the low-cost natural monofilament can beused, it is possible to reduce the manufacturing cost of the slidefastener. Furthermore, since the fastener element row can be dyed, it ispossible to easily deploy the matted fastener element rows of respectivecolors, thereby coping with a small-lot product.

According to the method for manufacturing a slide fastener of thepresent invention, the method for manufacturing the slide fastenerincludes the step of forming the monofilament by extrusion molding, thestep of forming the roughened surface having a number of concaves on thesurface of the monofilament by performing blast processing on thesurface of the monofilament, the step of shaping the monofilament intothe fastener element row; and the step of dying the fastener elementrow. Accordingly, it is possible to easily produce the slide fastenerhaving the fastener element on which both dying and matting areperformed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a front view depicting an embodiment of a slide fasteneraccording to the present invention;

FIG. 2 is a cross-sectional view depicting the surroundings of onefastener element row shown in FIG. 1;

FIG. 3 is a perspective view of the fastener element row shown in FIG.2;

FIG. 4 is a cross-sectional view taken along line A-A in FIG. 2;

FIG. 5 is an enlarged cross-sectional view of part B in FIG. 4;

FIG. 6 is a photograph of the cross-section of FIG. 4;

FIG. 7 is an enlarged photograph of part C in FIG. 6;

FIG. 8 is a flowchart depicting a method for manufacturing a slidefastener according to the present invention;

FIG. 9 is an explanatory view depicting the process of forming aroughened surface having a number of concaves on the surface of amonofilament by performing blast processing on the surface of themonofilament;

FIG. 10 is an explanatory view depicting the process of shaping themonofilament into a fastener element row;

FIG. 11 is a photograph depicting the cross-section of a naturalmonofilament in dyed state;

FIG. 12 is an enlarged photograph of part D in FIG. 11;

FIG. 13 is a photograph depicting the cross-section of a naturalmonofilament in a state where the surface thereof is polished with usinga brush and dyed; and

FIG. 14 is an enlarged photograph of part E in FIG. 13.

EMBODIMENTS OF INVENTION

Hereinafter, an embodiment of a slide fastener and a method formanufacturing the same according to the present invention will bedescribed with reference to the accompanying drawings. In the followingdescription, as for the fastener tape, a front side refers to a nearside with respect to the paper surface of FIG. 1, a back side refers toa far side with respect to the paper surface of FIG. 1, an upper siderefers to an upper side with respect to the paper surface of FIG. 1, alower side refers to a lower side with respect to the paper surface ofFIG. 1, a left side refers to a left side with respect to the papersurface of FIG. 1, and a right side refers to a right side with respectto the paper surface of FIG. 1. As for a slider, an upper side refers toa near side with respect to the paper surface of FIG. 1, a lower siderefers to a far side with respect to the paper surface of FIG. 1, afront side refers to an upper side with respect to the paper surface ofFIG. 1, a rear side refers to a lower side with respect to the papersurface of FIG. 1, a left side refers to a left side with respect to thepaper surface of FIG. 1, and a right side refers to a right side withrespect to the paper surface of FIG. 1. In addition, as for the fastenertape and the slider, a left and right direction is also referred to as awidth direction. Furthermore, an up-down direction of the fastener tapeis also referred to as a longitudinal direction.

As shown in FIG. 1 and FIG. 2, a slide fastener 10 according to thisembodiment includes a pair of left and right fastener tapes 20; a pairof left and right fastener element rows 30 provided on respectiveopposing tape-side edges 20 a of the pair of left and right fastenertapes 20, the fastener element rows having; a slider 40 configured toengage and disengage the pair of left and right fastener element rows 30with and from each other; a bottom end stop provided on the lower end ofthe pair of left and right fastener element rows 30; and a pair of leftand right top end stops 12 provided on respective upper ends of the pairof left and right fastener element rows 30. In addition, the bottom endstop 11 may be substituted with a separable end stop which includes aninsert pin, a box pin and a box body.

As shown in FIG. 2 and FIG. 3, each fastener element row 30 is acoil-shaped fastener element row which is formed by winding in apredetermined direction a monofilament 50 made of synthetic resin, whichwill be described later, and includes a plurality of fastener elements31. A core string 32 is inserted into the fastener element row 30 andthe fastener element row 30 is sewn to the upper surface of thetape-side edge 20 a of the fastener tape 20 using a sewing thread whichis subjected to double chain stitch. In the meantime, the fastenerelement row 30 may be a fastener element row in which the monofilament50 made of synthetic resin is formed into a zigzag shape. In addition,synthetic resin materials for the monofilament 50 may include polyester,nylon and the like.

Each fastener element 31 includes an engagement head section 31 a whichengages with and disengages from a counterpart fastener element 31, anupper leg section 31 b which extends outwardly in the width directionfrom the upper end of the engagement head section 31 a, a lower legsection 31 c which extends outwardly in the width direction from thelower end of the engagement head section 31 a, and a connecting section31 d which connects the outer end of the upper leg section 31 b in thewidth direction with the outer end of the lower leg section 31 c of theadjacent fastener element 31 in the width direction.

The slider 40 has an automatic stop function. When the slider 40 ismoved upward (in a direction away from the bottom end stop 11) bypulling a pull-tab 41, the left and right fastener element rows 30 whichare disengaged from each other are engaged with each other. When theslider 40 is moved downward (in a direction approaching the bottom endstop 11), the left and right fastener element rows 30 which are engagedwith each other are disengaged from each other.

In addition, in this embodiment, a roughened surface 52 having a numberof concaves is formed in the surface of the surface layer 51 which isformed on the surface of the monofilament 50 and which can be coloredwith dyes, by performing blast processing on the surface layer 51. Thus,as shown in FIG. 2 to FIG. 7, the roughened surface 52 having a numberof concaves is formed over the entire surface of the fastener elementrow 30 which is formed from the monofilament 50. The roughened surface52 having a number of concaves is formed by collisions of blastmaterials which are injected onto the surface of the surface layer 51during the blast processing, and is constituted by a large number ofmicroscopic blast marks which are formed in response to the collision ofthe blast materials. A large number of dots shown in FIG. 2 and FIG. 3show the roughened surface 52 having a number of concaves. In addition,the term “the surface layer 51 being able to be colored” means that thedyes can permeate into the surface layer 51.

In addition, the average roughness degree of the roughened surface 52 isset to the range from 0.1 μm to 6.0 μm, and preferably from 0.3 μm to3.0 μm. In order to obtain the average roughness degree ranging from 0.1μm to 6.0 μm, blast materials (e.g. stainless steel materials, aluminamaterials, steel materials or the like) having a particle diameterranging from 20 μm to 200 μm is used for the blast processing.

Here, as seen from FIG. 4, the surface layer 51 is formed so as to coverthe surface of the monofilament 50. The surface layer 51 has a thicknessranging from 10 μm to 30 μm. As shown in FIG. 5, the blast materialscollide against the surface layer 51, recess the surface layer 51 so asto have concave shapes in the thickness direction thereof withoutscraping the surface layer 51 and also recess an element body 53 so asto have concave shapes. The presence of the surface layer 51 can be moreclearly recognized when the surface of the monofilament 50 is coloredwith dyes. FIG. 6 and FIG. 7 are cross-sectional photographs that showthe surface layer 51 colored with dyes. FIG. 6 shows that the coloredsurface layer 51 exists at a predetermined thickness over the entireperiphery of the surface of the monofilament 50. In addition, FIG. 7shows that the surface layer 51 is formed into a concave-convex shapealong microscopic concaves and convexes which are formed on the elementbody 53.

A measuring instrument that is used for measuring average roughnessdegree is as follows:

>Surfcom 130A, a product available from Kabushiki Kaisha Tokyo Seimitsu(Accretech)

>Cutoff value: 0.25 mm

>Evaluation length: 1.25 mm

>Measurement speed: 0.3 mm/s

As described above, according to the slide fastener 10 of thisembodiment, the roughened surface 52 having a number of concaves isformed in the surface of the surface layer 51 of the monofilament 50.Consequently, it is possible to perform matting on the monofilament 50without scraping the surface layer 51. Accordingly, both dying andmatting can be performed on the fastener element row 30. In addition,since the low-cost natural monofilament 50 can be used, it is possibleto reduce the manufacturing cost of the slide fastener 10. Furthermore,since the fastener element row 30 can be dyed, it is possible to easilydeploy the matted fastener element rows 30 of respective colors, therebycoping with a small-lot product.

In sequence, a method for manufacturing a slide fastener according tothe present invention will be described.

As shown in FIG. 8, the method for manufacturing the slide fastener 10of this embodiment includes a process of forming a monofilament 50 byextrusion molding (step S1), a process of forming the roughened surface52 having a number of concaves on the surface of the surface layer 51 ofthe monofilament 50 by performing blast processing on the surface of themonofilament 50 (step S2), a process of shaping the monofilament 50 intothe fastener element row 30 (step S3), and a process of dying thefastener element row 30 (step S4). In the meantime, the fastener elementrow 30 is attached to the fastener tape 20, between the element-shapingprocess of step S3 and the dying process of step S4. The fastenerelement row 30 and the fastener tape 20 are fed to a sewing machine,which in turn stitches the fastener element row 30 to the tape-side edge20 a of the fastener tape 20 using a sewing thread 33.

In addition, in the surface-roughening process of step S2, as shown inFIG. 9, blast materials 62 are injected from nozzles 61 and 61 of a shotblast device onto the surface of the monofilament 50 after the extrusionmolding process of step S1, thereby forming the roughened surface 52 onthe surface of the surface layer 51 of the monofilament 50.

In addition, in the element-forming process of step S3, as shown in FIG.10, first, the monofilament 50 after the surface-roughening process ofstep S2 is wound on a mandrel 71 of an element-forming device into theshape of a coil. Then, the monofilament 50 which is wound on the mandrel71 is transported while being held between screw grooves of an opposingscrew 72. Afterwards, the coil-shaped monofilament 50 which is beingtransported on the mandrel 71 is converted into the fastener element row30 by beating portions of the coil-shaped monofilament 50 which are tobe the engagement head sections 31 a using a pressing roller 73 so thatthe beaten portions are shaped into the engagement head sections 31 a.

In the dying process of step S4, the fastener element row 30 attached tothe fastener tape 20 is disposed inside a dying vessel, and dyingsolution is poured into the vessel, so that the fastener element row 30and the fastener tape 20 are immersed in the dying solution. At thistime, the dying solution is heated at a predetermined temperature (from100° C. to 150° C.). Consequently, the dye permeates into and is fixedto the surface layer 51 of the monofilament 50 of the fastener element30.

As described above, the method for manufacturing the slide fastener 10according to this embodiment includes the process S1 of forming themonofilament 50 by extrusion molding, the process S2 of forming theroughened surface 52 having a number of concaves on the surface of thesurface layer 51 of the monofilament 50 by performing blast processingon the surface of the monofilament 50, the process S3 of shaping themonofilament 50 into the fastener element row 30, and the process S4 ofdying the fastener element row 30. Thus, it is possible to easilyproduce the slide fastener 10 having the fastener element 30 on whichboth dying and matting are performed.

DESCRIPTION OF REFERENCE NUMERALS

-   -   10 Slide Fastener    -   20 Fastener Tape    -   20 a Tape-Side Edge    -   30 Fastener Element Row    -   31 Fastener Element    -   40 Slider    -   50 Monofilament    -   51 Surface Layer    -   52 Roughened Layer    -   S1 Extrusion Molding Process    -   S2 Surface-Roughening Process    -   S3 Element-Shaping Process    -   S4 Dying Process

The invention claimed is:
 1. A method for manufacturing a slide fastenercomprising: a pair of fastener tapes; a pair of fastener element rowsprovided on respective opposing tape-side edges of the pair of fastenertapes, the pair of fastener element rows having a plurality of fastenerelements; and a slider configured to engage and disengage the pair offastener element rows with and from each other, wherein each of the pairof fastener element rows is comprised of a monofilament which is made ofsynthetic resin, the method comprising: a step of forming themonofilament by extrusion molding, the monofilament having a surfacelayer on a surface thereof, the surface layer being able to be coloredwith dyes; a step of forming a roughened surface having a number ofconcaves on the surface of the monofilament by performing blastprocessing on the surface of the monofilament; a step of shaping themonofilament into the fastener element row; and a step of dying thefastener element row, wherein the surface layer has a thickness rangingfrom 10 μm to 30 μm, and an average roughness degree of the roughenedsurface is less than a thickness of the surface layer.
 2. The method formanufacturing a slide fastener according to claim 1, wherein the averageroughness degree of the roughened surface ranges from 0.1 μm to 6.0 μm.3. The method for manufacturing a slide fastener according to claim 1,wherein a particle diameter of blast materials used for the blastprocessing ranges from 20 μm to 200 μm.
 4. The method for manufacturinga slide fastener according to claim 1, wherein blast materials used forthe blast processing are made of one of stainless steel, alumina andsteel.